Method and apparatus for making a saw blade



July. 18, 1967 A. J. KANE 3,331,255

METHOD AND APPARATUS FOR MAKING A SAW BLADE Original Filed April 26,1963 Sheets-Sheet 1 INVENTOR. ALBERT J. KANE ATTORNEYS Juiy 18, 1967 A.J. KANE METHOD AND APPARATUS FOR MAKING A SAW BLADE 3 Sheets-Sheet 2'Original Filed April 26, 1963 FIG. /0

INVENTOR. ALBERT J. KANE ATTORNEYS July 1 8, 1967 A. J KANE METHOD ANDAPPARATUS FOR MAKING A SAW BLADE Original Filed April 26, 1963 3Sheets-Sheet 5 INVENTOR. ALBERT J. KANE TTQBNEXS United States Patent3,331,265 METHOD AND APPARATUS FOR MAKING A SAW BLADE Albert J. Kane,Rockville, Conn., assignor to The Capewell Manufacturing Company,Hartford, Conn., a corporation of Connecticut Continuation ofapplication Ser. No. 275,816, Apr. 26, 1963. This application Mar. 11,1965, Ser. No. 446,766

8 Claims. ('Cl. 76112) This application is a continuation of my priorapplication Ser. No. 275,816, filed Apr. 26, 196-3, now abandoned.

The present invention relates to an improved and novel method andapparatus for milling the teeth of the saw blades.

An object of this invention is to provide a novel method formanufacturing saw blades by which method burr-free saw blades havingmilled cutting edges may be quickly and inexpensively produced.

Another object of this invention is to provide an improved apparatus formilling the teeth on a blank to form a saw blade. Included in thisobject is the provision of a novel milling cutter having a plurality ofaxial rows of milling teeth with the teeth in adjacent rows havingdifferent tooth forms and being staggered relative to each other.

Still another object of this invention is to provide a novel method formanufacturing saw blades wherein the gullet between adjacent teeth isenlarged for a given tooth size to provide an increased volume for chipsbetween adjacent teeth to reduce substantially the possibility of chipsjamming the saw.

Other objects will be in part obvious and in part pointed out more indetail hereinafter.

The invention accordingly consists in the features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereafter set forth and the scope of theapplication of which will be indicated in the appended claims.

In the drawings:

FIG. 1 is a side view of a portion of a saw blade involving theprinciples of this invention;

FIG. 2 is an enlarged fragmentary side View of the saw blade of FIG. 1showing in detail the novel tooth construction of this invention;

FIG. 3 is a top view of the teeth shown in FIG. 2;

FIG. 4 is a partial vertical cross section taken along line 4-4 of FIG.2;

FIG. 5 is a milling machine utilized in the practice of this invention;

FIG. 6 is a schematic view in cross section of the novel conical millingcutter of this invention;

PEG. 7 is a fragmentary end view partly shown in phantom of the millingcutter of FIG. 6;

FIG. 8 is an enlarged schematic view showing the details of constructionof the cutting teeth of the milling cutter of FIG. 6;

FIG. 9 is an enlarged fragmentary side view showing the teeth at anintermediate stage of construction;

FIG. 10 is a top view of the teeth shown in FIG. 9;

FIG. 11 is an end view taken along the line 1111 of FIG. 9; and 7 FIG.12 is an enlarged fragmentary view illustrating one aspect of themilling of teeth in accordance with this invention.

Referring now more specifically to the drawings wherein like parts aredesignated by like numerals throughout the various figures, a saw blade10 made in accordance with this invention is shown in FIG. 1. The sawblade 10 is preferably constructed of carbon or high-speed steel whichmay be heat treated if desired after the teeth have been formed ashereinafter described. The saw blade 10 ice includes a plurality ofcutting teeth 12, 14 along one longitudinal edge thereof.

Referring particularly to FIGS. 2, 3 and 4, the cutting toothconstruction resulting from the practice of this invention isillustrated. Since alternate teeth are formedin the same manner, onlytwo adjacent teeth 12, 14 will be described in detail. Each tooth 12 hasa leading face 16 and a trailing face 18, and each tooth 14 includes asimilar leading face 20 and a trailing face 22. As best shown in FIG. 2,the leading faces 16, 20' extend outwardly from the root of the toothand generally normal to the longitudinal axis of the blade. The trailingfaces 18, 22 are inclined to and intersect the leading faces 16, 20,respectively, to form cutting edges 36, 38. The leading faces 16, 20merge with an arcuate surface at the root of the tooth to form gullets24 between the teeth. The forward edge of the arcuate surface formingthe gullets 24 intersects the trailing faces 18, 22 at 26. It will beobserved that the arcuate surface forming the gullet 24 at the root ofthe teeth extends below the plane of trailing faces 18, 22 while theleading faces 16, 20 tangentially merge into the surface forming theenlarged gullet 24. It will thus be seen that this inventionincorporates an enlarged chip-receiving gullet 24 in a saw blade inwhich the surfaces of the teeth are formed entirely by milling ashereinafter more fully described.

The leading faces 16, 20 of teeth 12, 14 are disposed nonprependicularlyrelative to the sides 28 and 30 of the saw blade so as to provide anoblique fleam angle a as best shown in FIG. 2, and provide alternatecutting edges 32, 34 on opposite sides of the saw blades 10 in order toprovide a clean-sided cut or kerf in the workpiece being severed. Also,as best shown in FIGS. 2 and 3, the leading faces 16, 20 of teeth 12, 14are disposed rearwardly of a perpendicular to the longitudinal axis ofthe blade 10 by an angle [2 to provide a positive front rake for thetooth, and the trailing faces 18, 22 of the teeth are formed at anoblique angle 0 with the sides of the saw blade 10 and at an obliqueangle at with the edge of the blade to provide a clearance or back rakefor the teeth and to incline terminal cutting edges 36, 38 at an angleto the workpiece for efficient cutting action. Since the leading faces16, 26/ as well as the trailing faces 18, 22 of teeth 12, 14,respectively, are each milled, as hereinafter more fully described, thecutting edges 32, 34-, 36 and 38 are each sharpened along their fulllength in contrast to current practices in which the point only is sharpwith the result that the saw blade of this invention will cut theworkpiece more rapidly and has a longer life.

If desired, the teeth 12, 14 may, after being formed by milling, bealternately set or deformed laterally from the plane of the toothdependent upon the intended use of the saw blade.

Referring now to FIG. 5, there is shown a milling machine made inaccordance with this invention. As shown, the milling machine comprisesa supporting base 50' having mounted thereon a stationary platform 52which is provided with a longitudinal dovetail guide rail 54 whichcooperates with a complementary dovetail groove of table 56 to guide thetable 56 for longitudinal movement on the platform 52. Platform 52 maybe powered for longitudinal movement in both directions by any suitablemeans, not shown.

Laterally disposed relative to the table 56 is a housing 58 for thepower train, not shown, of the milling machine. A powered arbor or shaft60 is rotatably mounted in bearing 62 of housing 58 so as to extendlaterally across the table 56 and is connected to the output of thepower train in a conventional manner. Laterally extending from thehousing 58 above the arbor 60 is a stationary support arm 64 which has adownwardly depending portion which serves as a tail stock for supportingthe outer end of the 3 arbor 60 in a bearing 66. Mounted on the arbor 60is a conical milling cutter 68 which is shown schematically in FIG. 5.The milling cutter 68 is secured to the arbor 60 by anyhconven-tionalmeans, not shown, so as to rotate therew1t As shown in FIG. 5, a pair ofvises 70, 72 are fixedly mounted by any conventional means, not shown,at the ends of the table 56. The vises 70, 72 are each provided withrelatively movable jaws 74, 76. 'It will be observed that the jaw 76 ofeach of the vises is mounted for movement along the longitudinal axis ofthe table by being slidably mounted on a dovetail guide rail 78 on thestationary base 79 of the vise which engages a mating dovetail slot ofthe jaw 76. The jaws 74, 76 of the vises 70, 72 may be moved toward andaway from each other and secured in any adjusted position for holding aplurality of blanks for saw blades in side-by-side relationship by anyconventional means, not shown.

In accordance with one aspect of this invention, the vises 70, 72 areconstructed and arranged so as to hold the saw blade blanks 10 in apreselected compound angular relationship relative to the milling cutter68 and the table 56. Each of the vises is constructed so as to raise oneend of the blanks for saw blades 10 at an acute angle A relative to thetable 56. Since the table 56 is movable longitudinally in a planeparallel to the longitudinal axis of the milling cutter 68 and the arbor60, the angle A results in the upper end of the blades, as viewed inFIG. 5, being raised in a direction so as to converge in the directionof convergence of the milling cutter. As previously indicated, themilling cutter is conical in shape, and its outer surface is providedwith a taper angle B. Taper angle B is equal to angle A at which theblanks of saw blades 10 are secured relative to table 56.

It will further be observed that the vises 70, 72 each hold the blanksfor saw blades 10 at oblique angles C, C, respectively, relative to thelongitudinal axis of the table 56. The angles C, C are equal butopposite angles relative to the longitudinal axis of the milling cutter.

The vises 7 0, 72 also hold the blanks for saw blades 10 in a positionin which they are turned on their own longitudinal axis by a preselectedamount relative to perpendiculars to the top surface of table 56, asindicated by the angles D, D. Angles D, D are equal but opposite anglesrelative to perpendiculars to the top surface of the table 56.

Turning now to FIGS. 6, 7 and 8, there is shown a unique milling cuttermade in accordance with another aspect of this invention. The millingcutter, which is generally indicated by the numeral 68, is provided witha central bore 80 which is provided with a longitudinal keyway 82 fornonrotatably holding the milling cutter on the arbor 60. The outerperipheral surface of the milling cutter is shown as being in the formof a truncated cone and has a plurality of peripheral rows of cuttingteeth 84, 86 thereon. Each of the teeth 84 are identical in shape andare arranged in a plurality of rows of teeth about the periphery of themilling cutter with each of such rows in a plane perpendicular to thelongitudinal axis of the cutter. In like manner, each of the teeth 86are identical in shape and are arranged in a plurality of rows about theperiphery of the cutter with each of such rows being in a planeperpendicular to the longitudinal axis of the cutter. It will also benoted that the teeth 84 and the teeth 86 are of differentconfigurations, as best shown in FIG. 8, and the rows of teeth 84 andthe rows of teeth 86 are alternated longitudinally along the peripheryof the milling cutter 68. Further, as shown in FIG. 7, the teeth 84 arearranged in longitudinal rows, and the teeth 86 are also arranged inalternate longitudinal rows disposed between each pair of rows of teeth84. A longitudinal chip groove 85 is provided to space each of thelongitudinal rows of teeth.

Referring now particularly to FIG. 8, there is shown a schematicrepresentation of the teeth 84, 86 in which, for purposes of clarity ofillustration, the teeth 86 are shown in solid lines and the teeth 84 arein dotted lines. While,

as heretofore explained, the teeth 84 are arranged in longitudinal rowswhich are alternated with the longitudinal rows of teeth 86, therepresentations of the teeth 84 have been advanced to the same plane asthe teeth 86.

It will be observed that the leading edge 88 of the tooth 84 and theleading edge of the tooth 86 of the milling cutter are disposedperpendicularly to the longitudinal axis of the cutter. It will also beobserved that the trailing edge 92 of the tooth 84 and the trailing edge94 of the tooth 86 are disposed at an oblique angle to the longitudinalaxis of the cutter, although the included angles between the leading andtrailing faces of the teeth 84 and 86 are different for purposeshereinafter more fully described. The length of the leading edge 90 ofthe tooth 86 is greater than the radial length of the leading edge 88 ofthe tooth 84 and the arcuate tip of the tooth 86 has a greater radiusthan the arcuate tip of tooth 84.

While the peripheral rows of teeth 84, 86 are alternated, leadingcutting edges 88 and 90 are not equally spaced longitudinally of theaxis. As shown in FIG. 8, the distance X is less than the distance Y forpurposes hereinafter described.

The novel method for producing the saw blade 10 may be carried out bythe apparatus of FIG. 5 and the milling cutter of FIGS. 6-8.

While performing the method of this invention, a plurality of blanks forsaw blades 10 are gripped 1n side-by-side relationship in one of thevises 70, 72, say vise 70, at a compound angular disposition asindicated in FIG. 5. The table 56 is then moved longitudinally along theguide rail 54 of the milling machine past a rotating milling cutter 68,as shown in FIGS. 68 As the teeth 84, 86 of the milling cutter engagethe blanks for the saw blades 10, they fully form alternate teeth 12 asshown in FIGS. 9, l0 and 11 and finish mill the leading face 16 and thetrailing face 18 thereof and rough mill teeth 14. In addition, the tipof milling teeth 86 form alternate enlarged gullets 24 between theteeth.

It will be observed in FIG. 10 that the leading and trailing faces ofthe rough-milled tooth 14 is disposed at the same oblique angle as thecorresponding finish milled faces of the tooth 12. However, due to therelative longitudinal distance between X and Y as well as the relativelyacute angle of the trailing edge 94 of the milling cutter tooth 86 (FIG.8) to the leading edge 90 thereof, adequate stock is left on the leadingface of the rough-milled saw blade teeth 14 so that the teeth 12, 14 areequidistantly spaced in the finished product as indicated in FIG. 2. Inthis regard, it will be noted in FIG. 8 that the leading edge 90 of themilling cutter tooth 86 and the trailing edge 92 of the milling cuttertooth 84 finish mill the tooth 12 during the first pass of the blanksfor saw blades 10 past the milling cutter. It will also be noted thatbecause of the alternate placing of the longitudinal rows of millingcutter teeth 84 and milling cutter teeth 86 about the periphery of themilling cutter 68, this finish milling is accomplished by the alternateengagement of the cutting edge 90 of the milling cutter tooth 86 and thecutting edge 92 of the milling cutter tooth 84 to provide a burr-freeextremely sharp cutting edge along the entire length of all the cuttingedges of the tooth.

After the alternate teeth 12 are finish milled in a first pass past themilling cutter 68, as indicated above, the blanks for saw blades 10 are,in accordance with the illustrated novel method of this invention, movedlongitudinally relative to the longitudinal axis of the milling cutterby one tooth pitch and supported at a changed compound angle relative tothe milling cutter preparatory to a second pass past the milling cutter.In the apparatus shown in FIG. 5, this is accomplished by mounting thevise 72 at a distance E, which is equivalent to one tooth pitch, fromthe edge of the milling table 56. It will be observed that the vise 70is placed at the edge of the table 56, and, thus, the result is that thepartially milled saw blades are advanced one tooth pitch in thedirection of the longitudinal axis of the milling cutter. The vise 72also changes the angular disposition of the blades relative to the axisof the milling cutter and about their own axis by the angles of C and Dwhich are equal and opposite to the angles C and D at which the blanksfor the saw blades 10 were held during the first pass past the millingcutter. However, the angle A at which one end of the partially finishedsaw blades 10 are tipped up remains the same as during the first pass.

The partially milled saw blades 10 are then moved past the millingcutter 68 in a second pass, at which time the rough-milled teeth 14 arefinish milled as indicated in FIG. 12 and the alternate gullets 24 areformed by the tip of milling cutter teeth 86 to complete the milling ofthe saw blade 10.

From the foregoing, it will be apparent that this invention provides amethod of and apparatus for the finish milling of an extremely sharpburr-free saw blade having a positive forward rake and enlarged gulletsbetween the teeth by the use of a novel method of holding the blanks atpredetermined compound angles relative to a conical milling cutter. Themethod will al o accommodate the changing of the amount of positiveforward rake of the teeth without changing the cutter by changing theangles at which the saw blade blanks are held during the millingoperation. In this regard, the positive forward rake may be made greaterthan the taper of the milling cutter. For example, the use of a millingcutter having a 7 /2 taper with a blade being turned (angles D, D) andswung (angles C, C) 20 produces a saw blade having a 13 /2 positiverake. In addition, this method also provides a means for milling apositive rake on a saw blade using a milling cutter having forwardcutting edges which are perpendicular to its axis. The significance ofthis will be appreciated when it is considered that in conventionalmilling methods, the use of the similar teeth on a milling cutter canproduce only a positive rake equal to the taper of the cutter. Finally,the novel apparatus and milling cutter design of this invention areparticularly advantageous in carrying out applicants improved method.

As will be apparent to persons skilled in the art, various modificationsand adaptations of the structure abovedescribed will become readilyapparent without departure from the spirit and scope of the invention,the scope of which is defined in the appended claims.

I claim:

1. A method of forming a saw blade having alternately oppositely fleamedundercut teeth along one edge thereof comprising moving a blade blank ina first pass laterally past a conical milling cutter in a plane parallelto the cutter axis with the blank having its axis disposed at an acuteangle relative to its direction of movement past the cutter and to theplane of movement and rotated about its own axis so that the sidesthereof are nonperpendicular to the plane of movement to form aplurality of spaced finished teeth, moving the blade blanklongitudinally relative to the cutter axis by one tooth pitch, andmoving the blade blank in a second pass laterally past the cutter in thesame plane as the first pass with the axis of the blank being disposedat an equal but opposite angle relative to the cutter axis and rotatedabout its own axis to an equal and opposite angle relative to aperpendicular to the plane of movement to form finished teeth on theblank between the teeth formed during the first pass.

2. A method of forming a saw blade having alternately oppositely fleamedundercut teeth along one edge thereof comprising moving a blade blank ina first pass laterally past a conical milling cutter in a plane parallelto the cutter axis with the blank having its axis disposed at an acuteangle relative to its direction of movement past the cutter and at anangle relative to the plane of movement at least as large as to thetaper angle of the cutter and rotated about its own axis so that thesides thereof are nonperpendicular to the plane of movement to form aplurality of spaced finished teeth, moving the blade blanklongitudinally relative to the cutter axis by one tooth pitch, andmoving the blade blank in a second pass laterally past the cutter in thesame plane as the first pass with the axis of the blank being disposedat an equal but opposite angle relative to the cutter axis and rotatedabout its own axis to an equal and opposite angle relative to aperpendicular to the plane of movement to form finished teeth on theblank between the teeth formed during the first pass.

3. A method of forming a saw blade having alternately oppositely fleamedundercut teeth along one edge thereof comprising moving a blade blank ina first pass laterally past a conical milling cutter in a plane parallelto the cutter axis with the blank having its axis disposed at an acuteangle relative to its direction of movement past the cutter and rotatedabout its own axis so that the sides thereof are nonperpendicular to theplane of movement and having one end thereof raised above the plane ofmovement in the direction of convergence of the cutter and at an angleat least as large as the taper angle of the cutter to form a pluralityof spaced finished teeth, moving the blade blank longitudinally relativeto the cutter axis by one tooth pitch, and moving the blade blank in asecond pass laterally past the cutter in the same plane as the firstpass with the axis of the blank being disposed at an equal but oppositeangle. relative to the cutter axis and rotated about its own axis to anequal and opposite angle relative to a perpendicular to the plane ofmovement to form finished teeth on the blank between the teeth formedduring the first pass.

4. A method of forming a saw blade having alternately oppositely fleamedundercut teeth along one edge thereof comprising moving a blade blank ina first pass laterally past and in a plane parallel to a conical millingcutter having longitudinally extending rows of cutting teeth about theperiphery thereof with the teeth in alternate rows being staggered andhaving diiferent tooth shape with the blank having its axis disposed atan acute angle relative to its direction of movement past the cutter andto the plane of movement and rotated about its own axis so that thesides thereof are nonperpendicular to the plane of movement to form aplurality of spaced finished teeth and a plurality of rough milled teeththerebetween, moving the blade blank longitudinally relative to thecutter axis by one tooth pitch, and moving the blade blank in a secondpass laterally past the cutter in the same plane as the first pass withthe axis of the blank being disposed at an equal but opposite anglerelative to the cutter axis and rotated about its own axis to an equaland opposite angle relative to a perpendicular to the plane of movementto finish milling the rough milled teeth on the blank between the teethformed during the first pass.

5. A method of forming a saw blade having alternately oppositely fleamedundercut teeth along one edge thereof comprising moving a plurality ofside-by-side juxtaposed and edge aligned blade blanks as a unit in afirst pass laterally past a conical milling cutter in a plane parallelto the cutter axis with the blanks having their axes disposed at anacute angle relative to the cutter axis and to the plane of movement androtated about their own axes so that their sides are nonperpendicular tothe plane of movement to form over a predetermined length of the blanksa plurality of spaced finished teeth, moving the blade blankslongitudinally relative to the cutter axis by one tooth pitch, andmoving the blanks as a unit in a second pass laterally past the cutterin the same plane as the first pass with the axes of the blanks beingdisposed at an equal but opposite angle relative to the cutter axis androtated about their own axes to an equal but opposite angle relative toa perpendicular to the plane of movement to form finished teeth on theblanks between the teeth formed during the first pass.

6. A method of forming a saw blade having alternately oppositely fieamedundercut teeth along one edge thereof comprising moving a plurality ofside-by-side juxtaposed and edge aligned blade blanks as a unit in afirst pass laterally past a conical milling cutter in a plane parallelto the cutter axis with the blanks having their axes disposed at anacute angle relative to the cutter axis and to the plane of movement androtated about their own axes so that their sides are nonperpendicular tothe plane of movement to form over a predetermined length of the blanksa plurality of spaced finished teeth, moving the blade blankslongitudinally relative to the cutter axis by one tooth pitch, andmoving the blanks as a unit in a second pass laterally past the cutterin the same plane as the first pass but in the opposite direction withthe axes of the blanks being disposed at an equal but opposite anglerelative to the cutter axis and rotated about their own axes to an equalbut opposite angle relative to a perpendicular to the plane of movementto form finished teeth on the blanks between the teeth formed during thefirst pass.

7. A method of forming a saw blade having alternately oppositely fleamedundercut teeth along one edge thereof comprising moving a plurality ofside-by-side juxtaposed and edge aligned blade blanks as a unit in afirst pass laterally past a conical milling cutter in a plane parallelto the cutter axis with the blanks having their axes disposed at anacute angle relative to the plane of movement and rotated about theirown axes so that their sides are nonperpendicular to the plane ofmovement to form over a predetermined length of the blanks a pluralityof alternate finished teeth and a plurality of alternate rough milledteeth therebetween, moving the blade blanks longitudinally relative tothe cutter axis by one tooth pitch, and moving the blanks as a unit in asecond pass laterally past the cutter in the same plane as the firstpass but in the opposite direction with the axes of the blanks beingdisposed at the same angle relative to the plane of movement and rotatedabout their own axes to an equal but opposite angle relative to aperpendicular to the plane of movement to finish milling the roughmilled teeth on the blank between the teeth formed during the firstpass.

8. A method of forming a saw blade having alternately oppositely fieamedundercut teeth along one edge thereof comprising moving a blade blank ina first pass laterally past and in a plane parallel to a conical millingcutter having longitudinally extending rows of cutting teeth about theperiphery thereof with the teeth in alternate rows being staggered andhaving diflFerent tooth shape with the blank having its axis disposed atan angle of about 20 relative to its direction of movement past thecutter and at an angle at least as large as the taper angle of thecutter above the plane of movement and rotated about its own axis anangle of about 20 to form a plurality of spaced finished teeth and aplurality of rough milled teeth therebetween, moving the blade blanklongitudinally relative to the cutter axis by one tooth pitch and movingthe blade blank in a second pass laterally past the cutter in the sameplane as the first pass with the axis of the blank being disposed at anangle of about 20 but in the opposite direction relative to the cutteraxis and rotated about its own axis to an angle of about 20 but in anopposite direction relative to a perpendicular to the plane of movementto finish milling the rough milled teeth on the blank between thefinished teeth formed during the first pass.

References Cited UNITED STATES PATENTS 842,903 2/1907 Napier 76-441,433,306 1/1924 Slater 29-103 1,480,627 1/1924 Muller 76112 1,932,22310/1933 Lundquist 7625 2,762,242 9/ 1956 Thompson 7643 3,023,645 3/1962Craven 76-25 FOREIGN PATENTS 565,136 11/1932 Germany.

HARRISON L. HINSON, Primary Examiner.

1. A METHOD OF FORMING A SAW BLADE HAVING ALTERNATELY OPPOSITELY FLEAMEDUNDERCUT TEETH ALONG ONE EDGE THEREOF COMPRISING MOVING A BLADE BLANK INA FIRST PASS LATERALLY PAST A CONICAL MILLING CUTTER IN A PLANE PARALLELTO THE CUTTER AXIS WITH THE BLANK HAVING ITS AXIS DISPOSED AT AN ACUTEANGLE RELATIVE TO ITS DIRECTION OF MOVEMENT PAST THE CUTTER AND TO THEPLANE OF MOVEMENT AND ROTATED ABOUT ITS OWN AXIS SO THAT THE SIDESTHEREOF ARE NONPERPENDICULAR TO THE PLANE OF MOVEMENT OF FORM APLURALITY OF SPACED FINISHED TEETH, MOVING THE BLADE BLANKLONGITUDINALLY RELATIVE TO THE CUTTER AXIS BY ONE TOOTH PITCH, ANDMOVING THE BLADE BLANK IN A SECOND PASS LATERALLY PAST THE CUTTER IN THESAME PLANE AS THE FIRST PASS WITH THE AXIS OF THE BLANK BEING DISPOSEDAT AN EQUAL BUT OPPOSITE ANGLE RELATIVE TO THE CUTTER AXIS AND ROTATEDABOUT ITS OWN AXIS TO AN EQUAL AND OPPOSITE ANGLE RELATIVE TO APERPENDICULAR TO THE PLANE OF MOVEMENT TO FORM FINISHED TEETH ON THEBLANK BETWEEN THE TEETH FORMED DURING THE FIRST PASS.